hutchinson_1988#

M. H. R. Hutchinson and K. M. M. Ness, “Laser-induced continuum structure in xenon”, Phys. Rev. Lett. 60, 105 (1988)

Source record · Catalogue · Review register

Source kind: measurement

Recorded technique: Laser-induced continuum structure (LICS) in xenon: (2+1) three-photon ionisation through the two-photon resonance 5p6 -> 5p5 6p (J = 0) at 249.63 nm (a frequency-doubled, KrF-amplified dye laser, omega_1, 0.5 mJ), with a second dye laser (omega_d, ‘lambda_d ~ 401.73 nm’, 1.5 mJ) coupling the 5p5 10p (J = 0) level to the continuum at 3 hbar omega_1. Both lasers single or two longitudinal mode (bandwidth ‘estimated’ 100 MHz, 1 GHz with a second mode), near-Gaussian 12 ns pulses, focused together by one lens into an ionisation chamber with guard rings, xenon at 5-10 Torr. The total ion signal is recorded against omega_d with omega_1 held on the two-photon resonance (Fig. 4).

Materials in structured entries: None recorded.

Dataset quantities: None recorded.

Contents: 0 datasets; 0 formulas.

Curation notes#

Nothing extracted: no value of a quantity is printed. Phys. Rev. Lett. 60(2), 105-107 (11 January 1988) = PDF pages 1-3 (journal page = PDF page + 104); a scan, each page one image with a text layer. Identity checked against the first page (journal, volume, number, date, title, authors, received 28 July 1987). The text and Fig. 4 were read from the rendered pages.

WHAT IS PRINTED. The weak-field Fano profile R(e) = (q + e)^2/(1 + e^2), e the detuning in units of the half width Gamma_ke ~ pi |V_ke|^2 with V_ke = -d_ke . E_d (p. 105); q is ‘the ratio of the real to imaginary parts of the two-photon Rabi frequency’, the real part increased by Raman coupling through real bound states, which in xenon ‘does not make a significant contribution’ (p. 105), so ‘a small value of q’ is expected. The conditions for the structure (3 hbar omega_1 - hbar omega_d < E_IP) and for a background from nondegenerate 2 omega_1 + omega_d ionisation (2 hbar omega_1 + hbar omega_d > E_IP; E_IP < (5/2) hbar omega_1) (p. 106). Probe-only saturation (ground-state depletion) fixed the working range at ‘10-100 MW cm^-2’ (p. 107). Fig. 4 (p. 107): the ion signal (arbitrary units) against omega_d with a 10 GHz scale bar and no absolute frequency, (a) I_d = 80 MW/cm^2 with I_uv = 35 and 30 MW/cm^2, (b) I_d = 100 MW/cm^2 with I_uv = 40 and 35 MW/cm^2 and a 5 GHz bar: an asymmetric minimum and a broad peak (tang_1989, re-plotting (a), puts the minimum about 23 GHz below the peak), and a secondary peak of ‘approximately 5-GHz width’ on the low-frequency side whose origin ‘is not known’ (p. 107). No Fano q, width, shift, rate or cross section is fitted or printed, and the authors make no attempt to fit the profile (hutchinson_1989).

THE LEVELS (checked against nist_asd_2026, Xe_I_levels.tsv). ‘J = 0’ is 5p5(2P3/2) 6p[1/2]0, 80 118.962 cm^-1: two photons of 249.6288 nm (vacuum; 249.553 nm in air) reach it, so the printed 249.63 nm is the vacuum wavelength. With it, 3 omega_1 - omega_d at lambda_d = 401.73 nm (vacuum) is 95 286.10 cm^-1, 0.04 cm^-1 (1.2 GHz) from NIST’s 5p5(2P3/2) 10p[1/2]0, 95 286.06 cm^-1 (the vacuum wavelength that matches exactly is 401.7293 nm); read as an air wavelength, 401.73 nm would put the structure 7 cm^-1 away. So the dressed level is 10p[1/2]0 and both wavelengths are vacuum ones. 2 omega_1 + omega_d = 105 011 cm^-1 lies between the Xe+ 2P3/2 and 2P1/2 limits (97 833.787 and 108 370.80 cm^-1), as tang_1989 says; 3 omega_1 = 120 178 cm^-1 is above both.

WHAT BEARS ON OEP 8 (sections 4.3-4.4). (1) The experiment is a two-colour LICS: the interference is between the (2+1) ionisation of 6p[1/2]0 by omega_1 and the path through 10p[1/2]0 dressed by omega_d, not between OEP 8’s (2+1) and direct three-photon channels; it neither measures nor bounds the latter. (2) No light shift of 6p[1/2]0 or 10p[1/2]0 is printed: knight_1990 (TC-989, p. 52) cites this paper for Stark shifts ‘measured to be an order of magnitude less than the peak-to-window spacing’, but the Letter contains no such measurement or statement (FINDING); the nearest is tang_1989’s calculated ‘ac Stark shifts were found negligible’ at 30 and 80 MW/cm^2. TC-1010 requested this paper for ‘Xe LICS light shifts’: it has none. (3) The probe-only working range, 10-100 MW/cm^2 for 12 ns pulses of 0.1-1 GHz bandwidth at 5-10 Torr, marks where (2+1) ionisation through 6p[1/2]0 begins to deplete the ground state: a qualitative bound only (no fluence, spot size or ion yield is printed). tang_1989 puts the ionised fraction at 65-70 % at 30 and 80 MW/cm^2 (calculated).

NOT TAKEN. Fig. 4 (signal in arbitrary units, relative frequency only): a line shape, not a quantity, and its peak positions have no absolute frequency. Figs. 1-3: diagrams. Further data cited, not in the library: M. H. R. Hutchinson and K. J. Thomas, IEEE J. Quantum Electron. 19, 1823 (1983) (resonant frequency mixing); D. Feldmann, G. Otto, D. Petring and K. H. Welge, J. Phys. B 19, 269 (1986) (LICS in sodium). No two-photon strength or cross section is printed.

Recorded bibliographic identity status: VALIDATED_WITH_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents.

Datasets#

No datasets are recorded.

Formulas#

No formulas are recorded.

Corrections#

No dataset errata are recorded in this source record.

Formula corrections, where recorded, appear with their formulas above. Curation notes may also discuss corrections or unresolved interpretation. Consult the review register for the checks and decisions.